Many types (i.e., classes) of events occur in a database system. Examples of different classes of events that occur include modifications to a database object (such as a table), a database instance crash, and changes to the state of a message queue. Users, such as administrators, may register to be notified of certain events. Reporting events to such registrants is increasingly becoming a common activity in database systems. It would be desirable to provide an efficient mechanism to process such database events.